A Vancouver, Washington, teen was reported missing Sunday night after she embarked on a naked "spiritual quest" and never returned.

19-year-old Maureen Kelly was camping with friends at the Canyon Creek Campground in Gifford Pinchot National Forest when she decided to set off on a "spiritual quest" while wearing nothing but a fanny pack with a few survival items.

"She had talked about doing this spiritual quest for evidently quite some time," said Skamania County Undersheriff Dave Cox. "The folks that she was with, they felt that this was something she needed to do."

Kelly didn't tell her friends when they should expect her back, but when she failed to return by midnight, a member of the group decided to alert the authorities.

Though she was carrying a pocket knife, a compass, and some matches in her fanny pack, Kelly's brother said his sister was "not as prepared as he would have liked" for the great outdoors.

Additionally, the area Kelly was hiking into is known for being particularly steep, with heavy timber and brush.

"It's called Canyon Creek Campground for a reason," said Sharon Ward of Pacific Crest Search Dogs.

Undersherrif Cox also expressed concern that weather could become a factor in Kelly's "survivability," if temperatures continue to drop.

"The weather [Monday] night was in the mid to upper 40s," he told ABC News. "The cloud cover did move in, and so we're concerned that we might start getting some precipitation."

Cox noted that, while he did find Kelly's decision to leave camp in her birthday suit "a little bit unusual," there was "no indication" at this time that drugs were involved.

[screengrabs via KPTV]